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arXiv 1906.11289cs.LGstat.ML
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近似最优分层抽样

Near Optimal Stratified Sampling

Tiancheng Yu, Xiyu Zhai, Suvrit Sra

摘要:

机器学习系统的性能通常使用i.i.d.进行评估。用真实的标签观察。然而,获取地面真实标签是昂贵的,而获得未标记的样本可能更便宜。分层抽样在这种情况下是有益的,可以减少所需的真实标签的数量,而不会影响评估的准确性。分层采样利用统计特性(例如,方差),尽管通常是在不切实际的假设下,即这些属性是已知的。我们提出了两个新的算法,同时估计这些属性和优化的评估精度。我们构造了一个下界,以表明所提出的算法(对数因子)是速率最优的。合成和真实数据上的实验表明,我们的算法能够降低标签的复杂性。

英文摘要:

The performance of a machine learning system is usually evaluated by using i.i.d.\ observations with true labels. However, acquiring ground truth labels is expensive, while obtaining unlabeled samples may be cheaper. Stratified sampling can be beneficial in such settings and can reduce the number of true labels required without compromising the evaluation accuracy. Stratified sampling exploits statistical properties (e.g., variance) across strata of the unlabeled population, though usually under the unrealistic assumption that these properties are known. We propose two new algorithms that simultaneously estimate these properties and optimize the evaluation accuracy. We construct a lower bound to show the proposed algorithms (to log-factors) are rate optimal. Experiments on synthetic and real data show the reduction in label complexity that is enabled by our algorithms.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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